GE PanaFlow MV80, User Manual

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PanaFlow™ MV80 & MV82 User’s Manual 5
Chapter 1. Introduction
1.3.3 Flow Velocity Range (cont.)
As shown in Figure 3 below, PanaFlow meters exhibit a constant Strouhal number across a large range of Reynolds
numbers, indicating a consistent linear output over a wide range of flows and fluid types. Below this linear range, the
intelligent electronics in PanaFlow automatically corrects for the variation in the Strouhal number with the Reynolds
number. The meter's smart electronics corrects for this non-linearity via its simultaneous measurements of the process
fluid temperature and pressure. This data is then used to calculate the Reynolds number in real time. PanaFlow meters
automatically correct down to a Reynolds number of 5,000.
Figure 3: Reynolds Number Range for the PanaFlow MV
1.4 Temperature Measurement
PanaFlow Flowmeters use a 1000 ohm platinum resistance temperature detector (PRTD) to measure fluid temperature.
1.5 Pressure Measurement
PanaFlow Flowmeters incorporate a solid-state pressure transducer isolated by a 316 stainless steel diaphragm. The
transducer itself is micro-machined silicon, fabricated using integrated circuit processing technology. A nine-point
pressure/temperature calibration is performed on every sensor. Digital compensation allows these transducers to
operate within a 0.3% of full scale accuracy band within the entire ambient temperature range of –40°F to 140°F
(–40 to 60°C). Thermal isolation of the pressure transducer ensures the same accuracy across the allowable process
fluid temperature range of –330°F to 750°F (–200 to 400°C).
0.0
0.1
0.2
0.3
10 3 10 4 10 5 10 6 10 7 10 8
Linear Range
Corrected Range
5000 Reynolds Number, Re
Strouhal Number, St